A vise is a mechanical screw apparatus used to hold or clamp a work piece in place while work is performed on it with tools such as saws, drills, mills, screwdrivers, etc. A vise typically has a fixed jaw that remains stationary, while a moving jaw in parallel relationship to the fixed jaw is moved towards or away from the fixed jaw by means of a screw.
An engineer's vise is used in metal-working applications. It is made from case steel or malleable cast iron for strength. Its jaws may constitute separate pieces made from soft or hard metal, depending upon the nature of the work piece and work operation to be performed on it. Hard jaws featuring serrated or diamond teeth provide good gripping to hold the work piece in place. But, their hard surfaces applied under pressure by the operator to the work piece can deform or mar the surface of the work piece—particularly given the serrations or diamond teeth on the hard jaw, or over-tightening of the hard jaw by the operator. Thus, soft jaws made with a smooth face from a soft metal like aluminum or plastic or wood are typically used to hold more delicate work pieces. Soft jaws may also be provided in advance with specially pre-shaped contours for holding the specific exterior shape of the work piece.
Hard jaws and soft jaws can wear out over time to the point that they no longer securely hold a work piece, and need to be replaced. Moreover, because soft jaws may have their working surfaces that engage the work piece specifically pre-shaped to match the contour of the work piece, they will not accommodate other work pieces having a different shape. This means that the soft jaw needs to be changed to a differently shaped soft jaw if the operator is switching between different types of work pieces during a work day.
Many different methods are known in the industry for attaching the soft jaw to the fixed jaw or movable jaw portion of the vise. For example, the soft jaw can be bolted securely to the fixed jaw or movable jaw. But, this bolted arrangement can make it difficult and time-consuming for an operator to switch between different types of soft jaws.
U.S. Pat. No. 530,733 issued to Tower in 1894 shows a different securement means by which a steel faced hard jaw and the movable jaw or fixed jaw have cooperating shaped surfaces that allow the two jaw portions to be attached to one another to form a mortise joint. A spring-loaded key contained inside a channel in the vise body engages the hard jaw to provide additional securement. However, the multiple ribs and recess of the mortise joint must be carefully milled into both the hard jaw and jaw portion of the vise so that the two pieces closely cooperate to form the mortise joint. Moreover, the mortise surface of the hard jaw must be carefully slid into engagement along the mortise surface of the vise body portion to join the two pieces, which makes their joinder a time-consuming affair requiring manual dexterity by the operator.
U.S. Pat. No. 3,341,190 issued to Adamson discloses a vise assembly in which supplemental jaws featuring an outwardly trapezoidally-shaped “V-guide” protrusion are bolted to the movable jaw and fixed portion of the vise. The hard jaw plates feature a mating slot having the same shape as the V-guide protrusion so that the hard jaw plate is slid into engagement with the supplemental plate from above. A locking member with a cam member provides additional securement means between the hard jaw plate and the supplemental plate.
U.S. Pat. No. 3,565,417 issued to Degle and U.S. Pat. No. 4,437,654 issued to Chiappetti show a different arrangement in which the interchangeable jaw member has a pair of L-shaped arms that engage mated slots in the vise support block when the jaw member is slid into engagement with the vise support block from above. This is a hard jaw with diamond-shaped grooves where the operator will tighten the vise around the hard work piece, so an additional locking cam member or spring loaded key is unnecessary for securing the interchangeable jaw member to the vise body support.
U.S. Pat. No. 3,685,817 issued to Worthington discloses a vise having a jaw member that pivots with respect to the vise body by means of pins on the vise body engaging slots formed in the jaw member. The two opposing jaw members on the closed vise pivot into engagement with a conically-shaped work piece.
U.S. Pat. No. 4,898,371 issued to Mills et al. discloses yet another arrangement in which the detachable jaw plates have formed within them T-shaped slots. Bolts having a T-shaped head extending from the vise body engage these slots as the detachable jaw plate is placed against the vise body and slide so that the T-shaped slots engage the corresponding T-shaped bolts. See also U.S. Pat. No. 6,971,643 issued to Garrison; U.S. Pat. No. 4,861,010 issued to Neil; U.S. Pat. No. 6,022,010 issued to Bernstein; and U.S. Pat. No. 4,960,270 issued to Fitzpatrick.
U.S. Pat. No. 4,798,371 issued to Wallisser illustrates a similar concept in which the detachable jaw features a T-shaped groove, while the vise body (movable jaw and fixed jaw) features a T-shaped rib protrusion that mates with the T-shaped groove. But once again, the detachable jaw must be slid along the vise body jaw from its end, so that frontal engagement of the detachable jaw with the vise body is impossible. This makes it more difficult to remove a jaw from the vise body and attach a new or replacement jaw. Pins and spring-loaded ball catches are additionally required by Wallisser for supplemental attachment of the detachable jaw to the vise body.
Two vise assemblies containing a dovetailed joint between the detachable jaw and the vise body are disclosed in U.S. Pat. No. 1,488,559 issued to Simokaitis and U.S. Pat. No. 5,649,694 issued to Buck. But, these references show a very close fit between the detachable jaw and the vise body along the dovetailed joint. This requires close milling of the parts and attachment of the detachable jaw from the end of the vise body. A crowded machine shop, however, may make this end loading of the detachable jaw to or from the vise body difficult or cumbersome where end access is impeded.
U.S. Pat. Nos. 5,065,990 and 5,150,888 both issued to Durfee disclose a vise where a cleat extending from a parallel positioning plate engages a slot formed in a removable jaw plate with a vertical bolt traveling through a base in the removable jaw plate into engagement with the cleat of the parallel positioning plate. These cleats and slots must closely match each other's shapes, and only end loading of the parallel positioning plate into engagement with the removable jaw plate is possible.
U.S. Published Patent Application 2012/0256362 filed by Ehnstrom discloses a quick-change vise jaw system in which a locking jaw is secured to the fixed or movable body of the vise by means of bolts. A soft jaw has a protruding dovetailed rib that fits into a slot in the face of the locking jaw. Several clamping nuts are raised or lowered by means of double-threaded bolts contained inside bores formed in the locking jaw so that the tapered bottom edge of the clamping nuts engage or disengage from the tapered edge of the dovetailed rib inserted inside the slot of the locking jaw.
The vise assembly of Ehnstrom does allow the soft jaw to be frontally attached to the locking jaw, instead of slid into engagement from the end. However, because of the relatively tight fit between the dovetailed rib and the groove of the Ehnstrom master jaw assembly, the clamping nuts must be substantially disengaged from contact with the dovetailed rib to provide the necessary clearance for frontal engagement or disengagement of the soft jaw from the locking jaw.
Another problem faced by users of vises is the challenge of positioning a work piece retained in the vise in proper alignment with a working tool. If a single work piece is placed in the vise to undergo work performed by a manually-operated tool like on a home work bench, then there is little difficulty because the user can manually adjust the position of the tool to properly perform the work on the work piece.
However, many manufacturers rely upon automated machine tools to perform repetitive operations on a work piece in an accurate manner. Such tools like drills, lathes, saws, milling machines, wood routers, and laser cutters are moved inside a computer numerical control turning center into a predetermined position and operated by means of computer-aided design (“CAD”) and computer-aided manufacturing (“CAM”) software programs that store a series of programmed commands for properly positioning and operating the tool. A number of different sizes of tools (e.g. drills, saws) or different types of tools may be contained in the CNC turning center to perform work upon a predetermined location on the work piece retained in a vise in direct response to those computer commands.
However, the efficiency of CNC-operated tools becomes quickly compromised if the work piece is not correctly positioned with respect to the fixed position of the tool defined by the computer commands. A master jaw assembly secured to the vise containing a soft jaw that is specifically contoured to hold the work piece in position provides a ready solution once the vise and its master jaw and soft jaw components are correctly positioned with respect to the computer-determined fixed position for the tool. A number of work pieces can then be serially inserted into the soft jaw to have the desired working tools perform their operations at predetermined locations on the work pieces in response to the computer commands.
But any manufacturing operation will inevitably need to switch between different jobs performed inside the CNC turning center. This will require the soft jaw to be detached from the master jaw and replaced with a differently-shaped soft jaw for the new job. This is the reason that soft jaws are used. But, if the user wishes to return to the former job order, then the former soft jaw not only must be installed in the master jaw, but also it must be installed in the precisely same position with respect to the master jaw, or else the work pieces will no longer properly line up with the fixed spatial position of the CNC-operated tools. If not properly aligned, the computer commands inputted into the CNC turning center must be changed in order to account for the new position of the soft jaw holding the work piece.
U.S. Pat. No. 4,898,371 issued to Mills et al. discloses a stopping plate that is screwed to the end of a fixed vise jaw member to assist with the orientation of a jaw blank attached to the face of the fixed vise jaw member by means of a cooperating cleat/T-shaped slot. But, this stopping plate cannot be easily moved into or out of position without installation or removal of a number of screws. U.S. Pat. No. 4,960,270 issued to Fitzpatrick discloses a stop mechanism that must be specially mounted to the top of the vise jaw by means of bolts. An adjustable alignment rod is retained in the stop mechanism by means of a set screw. However, this stop mechanism is also cumbersome to install and remove from the vise and only engages the work piece, itself, instead of a soft jaw to ensure proper alignment of the soft jaw with respect to a master jaw.
Therefore, providing a master jaw assembly in which a detachable jaw like a soft jaw or hard jaw can be frontally attached to the groove in the master jaw, and properly aligned with respect to the position of the master jaw for repetitive removal and attachment of the soft jaw or hard jaw would be very advantageous.